1. Field of the Invention
This invention relates to fluoropolymer compositions of polytetrafluoroethylene and other perfluoropolymers.
2. Description of Related Art
US 2004/0242783 A1 discloses a blend of tetrafluoroethylene/hexafluoropropylene copolymer, commonly called FEP, and polytetrafluoroethylene (PTFE), the PTFE imparting the improved extrusion property of reduced cone breaks during melt draw down extrusion coating of wire. The PTFE content of the blend is disclosed to be 0.03 to 2 parts by weight based on 100 parts by weight of the copolymer. When the amount of PTFE is more than 2 parts by weight, two disadvantageous results are disclosed: the melt viscosity of the blend increases significantly and the molded article tends to become brittle [0027]. These are the same effects as adding filler to a polymer, except that in the case of adding PTFE to FEP, the disadvantageous effects arise with even small additions of the PTFE to the FEP.